The present invention relates generally to systems for cleaning objects using high pressure fluid. Specifically, it relates to a vehicle mounted high pressure water cleaning apparatus.
A wide variety of apparatuses used for the delivery of high pressure water through a hose for cleaning various objects such as pipes are known in the art. Such high pressure systems include apparatus to deliver fluid such as water to a variety of pipes to clean debris and blockage from the pipes which may accumulate therein.
Such cleaning apparatuses for the cleaning of pipes and the like generally use water delivered through a hose, with the water being delivered at high pressure to more effectively clean any debris or blockages which may be present. Delivery of water at high pressure can create a number of problems with the systems used for its delivery. Typically, high pressure systems require special components designed to be used at high pressure, including hoses, nozzles, and pumps. Further, the change from high pressure to low pressure and back places a very large strain on the components of such a delivery system.
For example, when water is first delivered at high pressure, the strain on components such as nozzles can be immense, as the pressure does not build up gradually. Similarly, when a nozzle or valve is closed in such a system, a large pressure wave may be generated. This wave is sometimes referred to as a water hammer. Water hammers and sudden pressure changes, due to their extreme nature, can damage and destroy even high pressure components.
To combat these problems, systems may typically use a gradual buildup of pressure, and a gradual diminishing of pressure, when operating the system. This gradual buildup and release of pressure results in extra time being taken to perform a cleaning operation. Further, if cleaning must be stopped in mid process, even more time is added to the overall time taken by a cleaning. The longer each job takes, the fewer jobs can be done.
A further problem exists with the requirement of increasing and decreasing pressure frequently. Over time, the strain on a system subjected to this type of use will lead to a shorter life span of components. It would be desirable to provide a high pressure water cleaning system which is able to maintain a constant or near constant pressure load on its components.
Systems which use a gradual build up of water pressure also have problems with excess water spillage or leakage from the pipe being cleaned before adequate cleaning pressure is reached. This results in an undesirable cleaning operation. Sufficient pressure build up to clear a blockage may not be achieved until several minutes after a cleaning operation is begun.
It would further be desirable to provide a high pressure water cleaning apparatus that can generate a high pressure water stream very quickly, and without resultant damage to the components. It would also be desirable to provide such a system which can quickly stop high pressure water flow, again without resultant damage to the system.
Typical high pressure water cleaning systems use a length of hose extending from a hose supply, usually mounted on a truck or other vehicle. High pressure water is delivered through the hose. The controls for the apparatus are positioned at the vehicle. To properly clean pipes and the like, the outlet of the hose must be placed in the drain, and often is fed a distance into the pipe, cleaning as it is fed through the pipe. Since the hose end must be placed into a pipe, usually from the inside of a structure such as a building or a house, two operators are usually used in performing a cleaning operation. The first operator takes the hose into the structure and fits it into the pipe to be cleaned. The second operator remains at the control station to operate the controls, assuring appropriate pressure changes so as not to cause damage to the equipment. If only one operator is available, the startup and shutdown of a cleaning system may require numerous and frequent trips back to the controls of the system. This process results in extra time being taken to perform a cleaning operation. If two operators are used, the amount of time required may be reduced, but the total man hours for a cleaning operation is doubled for two operators.
Single operator systems are known in the prior art. However, single operator systems require a number of electrical cord connections and a control panel to allow the single operator to properly adjust the various systems of the cleaning apparatus, including pressure, pump speed, and the like. Since the typical cords for such adjustment and control functions are relatively short, a large amount of expense and effort must be undertaken in order to accomplish single operator use. It would be desirable to provide a cleaning system which may be operated by one operator, and which also has the added advantages of rapid high pressure operation discussed above.
Water for a cleaning operation is typically stored in a tank located on the vehicle. Such tanks have a limited capacity. When a cleaning operation must gradually increase pressure to the components, or gradually release pressure from components, excess water may be used. Further, if a single operator must return to the control station to begin or end a cleaning, further water may be wasted. Since water capacity is limited, the more water wasted, the more times a tank must be refilled. Refilling locations may be some distance from the site to be cleaned. It would be desirable then to provide a high pressure water cleaning system which minimizes water wastage.
Electrical power supplied to systems such as those described above may come from a variety of sources. If standard house electrical current from a 120 volt system is used, the potential for serious shock or even electrocution becomes possible. Since the components of a water cleaning apparatus necessarily come into frequent contact with damp or even wet situations, use of 120 volt electricity can be very dangerous. It would be desirable to provide a high pressure cleaning apparatus that reduces the potential for serious electric shock. Further safety features as remote shutoff switches and multiple redundancies would also be desirable.
Typical high pressure pumps utilized in apparatus for high pressure cleaning require large power supply to operate. These large pumps also generally require a large amount of room because they are typically run by an auxiliary engine sufficient to provide adequate power for their operation. Further, coupling of power from the vehicle transmission has been accomplished by using the vehicle transmission to operate a hydraulic system. Such a system has several problems. These include a significant loss of engine power through the hydraulic coupling, as well as the potential for a large spill of hydraulic fluid if hydraulic fluid lines under pressure burst. It would be desirable to provide a cleaning apparatus which can directly power a large jet pump from the drive train of the vehicle, without requiring the use of hydraulics or auxiliary engine.